Embodiments of the present invention generally relate to methods and systems for treating sleep apnea.
Sleep apnea is a common condition with serious consequences adversely affecting quality of life and overall health. It is comorbid with a number of other diseases including heart failure and obesity, and has been linked to increased risk of poor outcomes. A common treatment for sleep apnea is a Continuous Positive Airway Pressure (CPAP) device, which may provide benefit but with great inconvenience for the patient and for the patient's partner. Obstructive sleep apnea is the most common type of sleep apnea and is caused by the relaxation of the posterior tongue muscles that result in obstruction of the upper airways. Some surgical options exist for extreme cases, and several implantable devices seek to treat apnea, including hypoglossal nerve stimulation. Hyperglossal nerve stimulation results in the contraction of the posterior tongue muscles, and as a result, advances the tongue and unblocks the airway. This neurostimulation technique improves snoring, but is ineffective in the treatment of central sleep apnea.
However, conventional approaches for apnea treatment continue to have areas for improvement. For example, conventional systems generally utilize a mask, placed over the patient's face during sleep, to directly measure (and/or control) air entering and leaving the patient's airway passage. Wearing a mask during sleep is not desirable.
Also, conventional apnea stimulation treatment devices are battery powered. The batteries have a limited life cycle before requiring the device to be explanted. The useful life of the device battery varies with a size of the battery. Thus, a longer duration battery is relatively larger which in turn increases the size of the overall device.
Further, conventional stimulation systems treat apnea events generally, in that all types of apnea experienced by a patient receive a common stimulation therapy. However, different types of apnea events respond better to different types of therapy.
A need remains for methods and systems that are able to monitor for apnea episodes without directly interfering with the patient's airway passage. Also, a need remains for methods and systems that are able to discriminate between and selectively treat different types of sleep apnea events.
Further, a need remains for an implantable device for treating apnea, where the device life cycle and size are not dependent on batteries within the device.